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Comment by MarkusWandel | Hacker News Reader

This is somehow super retro cool. I remember the 8032 being the most serious computer I'd seen to date. Wordpro 4+ and something called "The Manager" in use at my high school, plus the rebadged daisywheel printer Commodore had at the time (CBM 6400?) just had "serious computer" written all over them, right before the IBM PC steamrollered all of that into oblivion.

100MHz. The software you could run! Add a megabyte or so of full speed, pageable RAM expansion. Every computer language right up to C++ (if it works on the 8-bit Arduino it could be shoehorned into a fast 6502 - limited stack? Who cares, just do the big stack in software. Special zero page? Just use it as glorified CPU registers).

What's the point really? But awesome all the same.

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A megabyte of ram on a machine with only a 16 bit address space gets a bit silly. Do you really want to manage 16 memory pages? These aren't multitasking machines, what are you going to do with that ocean of memory you can't access without faulting?

> These aren't multitasking machines

Why wouldn't a faster machine with more RAM be a multitasking machine? (Obviously without extras you are limited regarding security etc, but plenty early multitasking machines didn't have that)

Without a memory mapper or scheduler it's hard to write a multitasking OS.

Not in the sense we usually mean nowadays, but assigning pages to processes and switching between them, with a small non-paged segment for general data/code lets you build multitasking systems. E.g. I believe early multiuser BBSes ran on systems like that.

There were tools that added multitasking to the C64, such as e.g. BASIC Lightning that let you run multiple BASIC "threads" + sprite animations at the same time.

It's easy to write a scheduler for a 6502 as there's so little to save, though you'll need to be very careful about stack usage, and you might do better with a specialised scheduler (e.g. for C64 BASIC) as a lot of code you might want to run may store additional state in fixed locations.

Indeed. Consider that this was done even for some of the more primitive machines of the day —

https://en.wikipedia.org/wiki/MP/M

Back in the day, the typical use was as a RAMdisk.

[Z00M!] https://www.pagetable.com/?cat=18

A megabyte of ram on a machine with only a 16 bit address space gets a bit silly.

There were plenty of machines kitted out with that amount of RAM. S-100 bus and other multi-user systems in the 70's and 80's could handle dozens of simultaneous users. It's cooperative multitasking, not preemptive multitasking.

Well take Wordpro 4+ for example. In a 32K machine, it had enough memory for a few pages of text. It would have been relatively minor software complexity even at 1MHz to use paged memory to obtain a much bigger text buffer. Ditto BASIC could be readily rigged up to use a paged memory architecture. Not everything needs a linear address space.

> A megabyte of ram on a machine with only a 16 bit address space gets a bit silly. Do you really want to manage 16 memory pages?

The Game Boy Color has a 16-bit address space and almost all its games are 1MB or larger (although that's ROM rather than RAM). The largest game is 8MB in size - which is managed as 512 banks of 16KB each.

I can put 16MB on my c64 with my 1541 ultimate. Haven’t looked at ir much but I believe there were some commercial productivity apps such as GEOS with very basic multitasking capabilities would be well able use this. Imagine they’d had an amped up CPU too!

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